One-Shot Continuations and dynamic-wind

At a glance

(call/cc (lambda (escape) (escape 'done) 'unreachable))

Result

done

Current guarantees

• The first invocation atomically consumes the continuation before transfer; every later invocation is E340.
• dynamic-wind runs before, then thunk, then after; unwind runs pending after thunks innermost first.
• A new error or escape from an after thunk replaces the signal already in flight.

Boundaries

• Multi-shot continuation reuse and dynamic-context re-entry are deferred.
• Host exceptions and host continuations do not implement guest transfer.